Wednesday, December 24, 2008

Pop Evolutionary Psychology

David J. Buller is a Professor of Philosophy at Northern Illinois University (USA). He is an expert in his field, He is not a professional science journalist although he has written a book and many articles.

This is relevant because many science journalists have written favorable articles about popular evolutionary psychology. This is the field that promotes evolutionary explanations for many human behaviors. They are the classic examples of adaptationist just-so stories.

Some evolutionary psychologists have made widely popularized claims about how the human mind evolved, but other scholars argue that the grand claims lack solid evidence

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The most notable representatives of Pop EP are psychologists David M. Buss (a professor at the University of Texas at Austin and author of The Evolution of Desire and The Dangerous Passion) and Steven Pinker (a professor at Harvard University whose books include How the Mind Works and The Blank Slate). Their popular accounts are built on the pioneering theoretical work of what is sometimes referred to as the Santa Barbara school of evolutionary psychology, led by anthropologists Donald Symons and John Tooby and psychologist Leda Cosmides, all at the University of California, Santa Barbara.

According to Pop EP, “the human brain consists of a large collection of functionally specialized computational devices that evolved to solve the adaptive problems regularly encountered by our hunter-gatherer ancestors” (from the Web site of the Center for Evolutionary Psychology at U.C.S.B.). Just as evolution by natural and sexual selection has endowed all humans with morphological adaptations such as hearts and kidneys, Pop EP says, so it has endowed all humans with a set of psychological adaptations, or “mental organs.” These include psychological mechanisms, or “functionally specialized computational devices,” for language, face recognition, spatial perception, tool use, mate attraction and retention, parental care and a wide variety of social relations, among other things. Collectively, these psychological adaptations constitute a “universal human nature.” Individual and cultural differences are, by this account, the result of our common nature responding to variable local circumstances, much as a computer program’s outputs vary as a function of its inputs. The notable exceptions to this rule involve sex differences, which evolved because males and females sometimes faced distinct adaptive problems.

Moreover, because complex adaptation is a very slow process, human nature is designed for the hunter-gatherer lifestyle led by our ancestors in the Pleistocene (the period from 1.8 million to 10,000 years ago). As Cosmides and Tooby colorfully say, “our modern skulls house a Stone Age mind.” Pop EP proposes to discover our universal human nature by analyzing the adaptive problems our ancestors faced, hypothesizing the psychological mechanisms that evolved to solve them and then testing those hypotheses using standard-fare psychological evidence, such as paper-and-pencil questionnaires. Pop EP claims that a number of psychological adaptations have been discovered in this way, including evolved sex differences in mate preferences (males prefer nubility; females prefer nobility) and jealousy (men are more distressed by a mate’s sexual infidelity, women by emotional infidelity).

I believe that Pop EP is misguided. The ideas suffer not so much from one fundamental flaw as from many small mistakes. Nevertheless, recent critiques of evolutionary psychology point to some general problems of Pop EP.

There's nothing remarkable about this article. The majority of evolutionary biologists know full well that pop evolutionary psychology is a farce. For most biologists, it's an embarrassment.

The real puzzle is why most science journalists seem to be completely unaware of the controversy. They haven't been doing their job. Next time you see an article promoting the "latest discoveries" of pop evolutionary psychology look for the balance. Do you see the disclaimers questioning the relevance of the entire field? If those points aren't mentioned then you know that science journalists have not done their homework.

17 comments:

I bought that copy of Scientific American to read on the plane ride to my mom's house and I read the article that you linked to.

Whereas the article doesn't teach YOU anything new, it is valuable for someone like myself who is certainly a non-expert; as a result of reading this article I will certainly be more alert for such nonsense and will know which questions to ask myself.

I don't know what it is like at a university such as yours, but at mine it is common for non-scientists to make claims on baseless conjecture and pop-evolutionary biology seems to fall within that category.

"In science's pecking order, evolutionary biology lurks somewhere near the bottom, far closer to phrenology than to physics. For evolutionary biology is a historical science, laden with history's inevitable imponderables. We evolutionary biologists cannot generate a Cretaceous Park to observe exactly what killed the dinosaurs; and, unlike "harder" scientists, we usually cannot resolve issues with a simple experiment, such as adding tube A to tube B and noting the color of the mixture... If evolutionary biology is a soft science, then evolutionary psychology is its flabby underbelly."

Jerry Coyne is an ass. There is little difference between historical and non-historicla sciences. Both use the hypothetical-deductive method, as Mayr pointed out. Whether you use a lab coat or collecting data in the field is only a cosmetic difference. Predictions are made and ideas confirmed or discarded accordingly.

First off Jerry Coyne's contributions to the fields of speciation and sexual selection (among others) are significant and commendable. Secondly, why not just go read the article I linked to in order to get some context for that quotation? Obviously Dr. Coyne's opinion of his own field of research is not so low...

Yeah, well, there are many, many, many researchers that have made "significant contributions" in the fields of speciation and sexual selection, theoretitically and empirically. There is a lot of niches for studying that, and Coyne is just another in that list. I guess Coyne is a good evolutionary ecologist, but he is no towering figure of evolution.

Now, i can fully assure you this is by no menas the first time I hear him say something frivolous and stupid, and I very much doubt it will be the last.

I read Buller's article and I think he re-makes some excellent points. I was left with some questions, though:

Where is the line drawn between silly "pop" EP and the presumably legitimate academic version?

If the entire field of EP is founded on unjustifiable assumptions, then are scientific questions of human behavioral adaptations:a.) unanswerable in principle and therefore not worth asking?b.) only legitimate if hypothesized answers do not in any way imply ancestrally inequitable social situations?c. ) pointless because of the extreme behavioral plasticity of the amazing human brain? (an argument that seems to me a de facto blank-slate position)d.) or what?

If behavioral ecologists can identify patterns of social and sexual behavior that are consistent among anthropoids, primates, mammals, tetrapods, vertebrates, or animals (draw your own line), is it scientifically justifiable to investigate, as a hypothesis, that pattern in humans? If not, why not?

Ok, I need to make a precision: by "behavioral ecology" I mean the branch of ecologists that, much like in "evolutionary psychology" call themselves by a very general name, but actually represent only one opinion, an opinion contradicted by dissenting colleagues, which basically ignores the development of behavior by assuming its genetic determination. Gene selection explains the evolution of behavior. And that's it.

Well, it's not that simple, and other approaches exist (surprise!). In humans, it's called developmental psychology. In general, the term developmental systems biology has been proposed (by Oyama and others). These, of course, are evolutionary explanations, too. At all levels, human or not, the "gene assumption" has been sorely ignoring the complexities of behavioral and phenotypic plasticity.

No doubt there has been tons of research in behavioral ecology. The question is about the QUALITY of this research, which is low, specially given the self-satisfied atitude of this large, well-sustained community of researchers.

Most of the time it is just observation of a behavior, interpreted as some kind of optimal adaptive solution, and thus "must" be the result of gene selection. But it turns out it is quite often the result of behavioral plasticity, with no gene whatsoever to determining said behavior.

Other times it is just a measuremnet of heritability of a trait, usually very low (requiring for massive data sets to be detectted statistically) that is taken as evidence that the trait is "genetic"... and thus "must" be under selection. Amateurish stuff

Rarely are the assumptions put to test by achieving molecular resolution, actual sequences, for the genes "assummed" to be directing behavior

This is true that both historical and experimental sciences aim toward the same goal: finding the best model to explain an ensemble of data. The main differences stems from the numbers of possible data: in the field of experimental science, they are much more numerous, because there are no limits (other than fundings) to the possibilities of experimenting, and it is moreover possible to target very specific features of the systems, so that there is much INFORMATION at our disposal for validating our model.

In the case of historical sciences, the data are much sparser, it is most of the case a question of chance whether or not one finds something relevant for a theory, and in spite of the accumulation of more data with excavations (in the case of history/archeology) , the data are not sufficient for allowing the identification of one precise model, this is why in many fields of history, pluralism is a rule, because many possibilities could be true, and there is no way to differentiate between them-

Of course, there are several degrees of uncertainty, but in the case of EP, this seems to me to particularly problematic, since, as Jerry Coyne rightly pointed out, "Behaviors don't fossilize", so the few data available let much room for imagination to EPists. On the contrary, in fields like experimental chemistry or physic, models and possibilities are much more constrained because of the greater abundance of data.

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Superstition

Quotations

The old argument of design in nature, as given by Paley, which formerlyseemed to me to be so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being, like the hinge of a door by man. There seems to be no more design in the variability of organic beings and in the action of natural selection, than in the course which the wind blows.

Charles Darwin (c1880)Although I am fully convinced of the truth of the views given in this volume, I by no means expect to convince experienced naturalists whose minds are stocked with a multitude of facts all viewed, during a long course of years, from a point of view directly opposite to mine. It is so easy to hide our ignorance under such expressions as "plan of creation," "unity of design," etc., and to think that we give an explanation when we only restate a fact. Any one whose disposition leads him to attach more weight to unexplained difficulties than to the explanation of a certain number of facts will certainly reject the theory.

Charles Darwin (1859)Science reveals where religion conceals. Where religion purports to explain, it actually resorts to tautology. To assert that "God did it" is no more than an admission of ignorance dressed deceitfully as an explanation...

Quotations

I have championed contingency, and will continue to do so, because its large realm and legitimate claims have been so poorly attended by evolutionary scientists who cannot discern the beat of this different drummer while their brains and ears remain tuned to only the sounds of general theory.

The essence of Darwinism lies in its claim that natural selection creates the fit. Variation is ubiquitous and random in direction. It supplies raw material only. Natural selection directs the course of evolutionary change.

Rudyard Kipling asked how the leopard got its spots, the rhino its wrinkled skin. He called his answers "just-so stories." When evolutionists try to explain form and behavior, they also tell just-so stories—and the agent is natural selection. Virtuosity in invention replaces testability as the criterion for acceptance.

The first commandment for all versions of NOMA might be summarized by stating: "Thou shalt not mix the magisteria by claiming that God directly ordains important events in the history of nature by special interference knowable only through revelation and not accessible to science." In common parlance, we refer to such special interference as "miracle"—operationally defined as a unique and temporary suspension of natural law to reorder the facts of nature by divine fiat.

Quotations

My own view is that conclusions about the evolution of human behavior should be based on research at least as rigorous as that used in studying nonhuman animals. And if you read the animal behavior journals, you'll see that this requirement sets the bar pretty high, so that many assertions about evolutionary psychology sink without a trace.

Jerry Coyne
Why Evolution Is TrueI once made the remark that two things disappeared in 1990: one was communism, the other was biochemistry and that only one of them should be allowed to come back.

Sydney Brenner
TIBS Dec. 2000
It is naïve to think that if a species' environment changes the species must adapt or else become extinct.... Just as a changed environment need not set in motion selection for new adaptations, new adaptations may evolve in an unchanging environment if new mutations arise that are superior to any pre-existing variations

Douglas Futuyma
One of the most frightening things in the Western world, and in this country in particular, is the number of people who believe in things that are scientifically false. If someone tells me that the earth is less than 10,000 years old, in my opinion he should see a psychiatrist.

Francis Crick
There will be no difficulty in computers being adapted to biology. There will be luddites. But they will be buried.

Sydney Brenner
An atheist before Darwin could have said, following Hume: 'I have no explanation for complex biological design. All I know is that God isn't a good explanation, so we must wait and hope that somebody comes up with a better one.' I can't help feeling that such a position, though logically sound, would have left one feeling pretty unsatisfied, and that although atheism might have been logically tenable before Darwin, Darwin made it possible to be an intellectually fulfilled atheist

Richard Dawkins
Another curious aspect of the theory of evolution is that everybody thinks he understand it. I mean philosophers, social scientists, and so on. While in fact very few people understand it, actually as it stands, even as it stood when Darwin expressed it, and even less as we now may be able to understand it in biology.

Jacques Monod
The false view of evolution as a process of global optimizing has been applied literally by engineers who, taken in by a mistaken metaphor, have attempted to find globally optimal solutions to design problems by writing programs that model evolution by natural selection.